System and apparatus for assisting navigation



Aug. 22, 1933- w. N. FANNING 1,923,430

SYSTEM AND APPARATUS FOR ASSISTING' NAVIGATION Filed Jan. 21, 1930 IN VEN TOR. Wa/fer/V. Farm/1y Patented Aug. 22, 1933 UNITE-D SYSTEM AND APPARATUS FOR- Assis'rrNG NAVKGATIQN I r: FHCE This invention relates generally to apparatus for assisting navigation, particularlyjnavigation of ships atsea. f

7 It is a general object of the present invention 5 to devise a system and apparatus for use on ships which will tend v to prevent inaccuracies in .navigation, and which will utilize a minimum of apparatus for performing several desired functions.' i

Itis a further object of my invention to devise a method. and system utilizing apparatus which will serve to prevent ship-wrecks on shore or collision between vessels at sea by imparting a danger or warning signal of positive character to the operator, and which will give a warning signal in the event that certain apparatus becomes inoperative,

It is a further object of the present invention to devise a system of the above character which ventional commercial radio wave lengths used for communicating between ships, say :for ex-i ample in the neighborhood of 600 meters.

- It is a further object of thepresent invention toincorporate in a system of the -above character means whereby the apparatus can be, properly tested at regular intervals-to insure its proper operation, and which will make a record of its operation for occasional examination. It is another object of the present invention to devise a radio signaling system for use on ships which will be continuously operated to receive-signals, and which will incorporate both means for automatically translating a received danger signal, as for example an SOS code signal, and will alsogive a responseior alarm sig nal in the event that the, ship so equipped approaches in the proximity of another. ship or in proximity to a dangerous locality equipped with similar apparatus. V I

,It is another object of the present invention to devise a radio apparatus for aiding navigation, parts of which can also be utilized forreceiving submarine sound signals and for depth ranging. -It is a further object of the present invention to devise apparatuscapable of giving .a-visual and audible warning of the presence of submerging, submerged, or breaching submarine vessels, thus preventing collisions with vessels of this character. r J v 7 Further objects of the invention will appear from the following description in which I have set forth the preferred embodiment of my invention in conjunction with the accompanying drawing. It is to be understoodthat the ap can be utilized for continuous operation on con pended claims areto be accorded a rangelof equivalents consistent with the state'of. the prior art. 1 f f The radio apparatus which I utilize'in my sys term is preferably capable of simultaneouslyand 60, continuously transmitting and receiving radio signals. In the drawing such apparatus has been represented by the electron relay tube 11, of the Y usual three element type, connected with circuits so as to operate regeneratively. The. input or grid circuit 12 of relay 11 is coupled to a suitable tuned antenna circuit 13.. The output circuit 14 includes a coil';15, which can be coupled with the input circuit 12, so as to secure a feed back .of radio frequency energy.. A grid con- 7 denser and grid leak 16 has been shown inserted in the grid circuit of relay 11. Transformer 17 serves to couple the output of relay 11, to the input of an electron relay audio frequency amplis hair 18. Transformer 19 serves to couple the output of relay 18 with the electron relays 21, 22, and 23. As a source of B-battery current for. the outputs or plate circuits of relays 11 and '18 I have shown aB-battery'24, and a C-battery 26 is included for the purpose of maintaining a 80, properbias upon the grid. of relay 18. Translating means such as a pair of phones 27 have been shown inserted in. the output of amplifying relay 18, to enable monitoring by an operator.

Electron relays 21, 22 and ,23 arecontrolled ac- 5 cording to the amplified output currents from the v secondary of transformerlQ, and serve in turn to produce amplified currents for operating a magnetic relay 28. This relay is preferably one havingdiiferential magnetic windings 2'9. and 31.

Relay 21 has its grid connected with conductor 30, which in turn connects with the high potential secondary terminal of transformer 19.: The low potential terminal of this secondary can be conneoted to the negative terminalof C-battery 2 6, to properly. bias the grid of relay 21. The grid of relay 22 is likewise connected to conductor 30, and is therefore normally biased in the same man;-

ner ias-the'grid of relay 21... The control circuit for relays'21 and 22 has been shown completed by a conductor 25. J V 1 r The output circuit of relay 21 includes the series connected translating devices 33 and 34,

as for example relatively sensitivecurrent meters which can be read visually, andalsothewinding 29 of magnetic relay 28. The other magneticrelay winding 31 is included inthe plate or output a circuit of electron relay 23. As means for enersizing the outputs of bothelectronrelays 21 and 23,1 have shown'a B-battery 36 having its positive terminal connected to the point of connection between windings 29 and 31, and having its negative terminal connected to the common filament conductor 37 for the filament of relay 21, 22 and 23. The grid of electron relay 23 is connected to the negative terminal of a battery 38, the positive terminal of this battery being connected to the plate of electron relay 22.

Normally the bias provided by battery. 26, upon the grids of relays 21 and 22, is sufficient to make the plate filament impedance of these relays 21 and 22 substantially infinite. Thus no current flow normally occurs in the output of electron relay 21. With the plate filament impedance of electron relay 22 infinite, it is apparent that battery 38 will have no effect upon the grid of electron relay 23, so that this relay 23 acts as if its grid were disconnected or open ended. Thus a normal current flow will occur in the output circuitof electron relay 23, and thru magnetic wind- When a signal is received by electron relay 11, the integrated audio frequency modulations are impressed. upon amplifying relay "18, and the famplified current variations impressed upon the "grids of relays 21 and 22. Thus the grids of these relays become less negative or more'positive, so'thatthe plate'filament impedance of both relays becomes of finite value; Thus'when signal energy is being received, a normal current flow will occur thru'the indicating devices 33 and 34, and thru 'magnetic winding '29. At the same time since the plate filament impedance of electron relay 22*becomes finite, a circuit is formed for battery 38, so that this battery functions to place 'a negative bias upon the grid of electron relay 23 suflicientto' make the plate filament irn pedance' of this relay substantially" infinite. Therefore when signal energy is being received, a current 'flow occurs thru magnetic'winding 29,

and thru'devices 33 and 34, but the current fiow frequency when impressed upon relay 18. Relay 28 is of course ,adjt 1.sted ,so that its armature Will'not flutter in accordance with the audio fre quency variations.

The regenerative 11 is preferably made such thatthisrelay'and its associated circuit will not only serve as a detector of radiofrequency signals, but also-fasa transmitter of oscillations of substantially the same frequency; In other 'words this regenera tive detector serves to reradiate'radio'frequency energy to such an extentas to be effective'for 1G5 reception? by a like apparatus located within 'a given radius. In this connection itmay 'befexplained that I preferably provide 'a 'plurality 'of vessels with th'ef apparatus described above, so

that two vessels so equipped will"automatically exchange radioenergywhen theyapproach' in proximity to each other. In order: to-insure proper and simultaneousexchange of signals between two like systeni's suchlas described above, Ipreferably'periodicallyvary the tuning of the circuits associated with electron relayzll'." In'this operation of electron relay.

particular instance this is accomplished by providing a relatively small variable condenser 44, driven by suitable means such as a motor 46, and connected across the tuned input of electron relay 1i. Condenser 44 varies the tuning of the input of relay 11 within a given wave length channel, so that heterodyning with incoming signals from a like system, to secure an audiofrequency beat note for amplification, is insured. It is of course evident that when a plurality of such radio apparatus are installed upon diiferent ships, for simultaneous exchange of energy, it will be practically'impossible for the condensers 44 to be in absolute synchronism. Furthermore the variation in tuning afiorded by condensers 44 of two apparatus installed upon different ships, is not sufiicient to preclude reception of an audible frequency beat note. Thus assuming that two ships are. equipped with apparatus such as described above and are in proximity to each other so as to exchange radio energy, if the condenser 44 of one apparatus should at one instance be at maximum setting, and the condenser of the other apparatus at minimum setting, a varying beat notewculd still be secured by both apparatus.

While the apparatus described above may be arranged to operate uponany desired frequency channel, I preferably have it operating upon a commercial wave length channel of say 600 meters. This makes it possible to incorporate not only translating means for indicating the proximity of another vessel similarly equipped, or proximity to a radio station located on land, but also, to provide suitable means responsive to an SOS or similar radio distress signal. Thus I have shown a circuit 48 controlled by the armature and contact 42 of magnetic relay 28, and

which includes an SOS code selector 51. The output of selector 51 is connected to a magnetic relay 52, whichin turn serves to control a local alarm circuit 53. The selector 51 is constructed so as not to respond to ordinary telegraphic coding received by magnetic relay 28, but will respond to the coding of an SOS'signal, or equivalent conventional signal of distress. Thus when a distress signal is received, relay 52 isautomatically closed, to closethe alarm circuit 53, and thus apprise the operator'that a distress signal is being received- It is evident that when my apparatus comes into proximity with another similar apparatus, relatively long sustained signals will be received as distinguished from the interrupted impulses characterizing the conventional telegraphic code and SOS signals. 'In order to secure a characteristic indication responsive 'to such long sustained signals, I provide a delay relay 54, having its winding connected in series with circuit 48. The contacts-of relay 54control a local alarm circuit 56. The action of relay 54"is delayed to such an extent that it will not close this armature for ordinary telegraphic signals, or for SOS signals'. However when long sustained signals are received, relay 54 is operated to close the alarm circuit 56.

On many vessels apparatus is provided for transmitting and receiving submarine signals of audible frequency. Such apparatus is often employed for depth ranging, that is, to determine the depth of water beneath the vessel. In depth ranging sound Waves. of a definite frequency are generated by suitable apparatus and'directed downwardly. By detecting and noting the time lapse between. the instant the sound waves are transmitted, andthe'instant they are received,

thru the water when excited'with alternating current, and which will also serve to translate received sound waves into current variations. A circuit 59, including a source of current 61, serves to connect this device 58 with a suitable filter 62,

tuned to a definite audible frequency channel, say in the neighborhod of 1000 cycles. For exciting device58 to generate sound waves, I have indicated an oscillator or'alternating current generator 63 which can be connected to device 58 by closing key- 64. In place of providing separate and individual apparatus for translating the signals from circuit 59, I preferably utilize at least a portion of the radio signaling apparatus described above. Thus in practice. I can connect the tuned filter 62 to the input of audio frequency amplifier l8. Suitable means for effecting result consists of an audio frequency transformer 60, having its primary connected to tuned filter 62; One terminal of the secondary of transform er 60 is connected to an extra grid 65 of relay l3, and its other terminal connected to filament'oi electron relay 18 thru a suitable biasing battery 66. This particular means for connecting tuned filter 62 with electron relay 1.8 has been provided in order to utilize the amplifying characteristics of relayl8, and in order to obviate modulating the high frequency oscillations being generated by electron relay 11. I

In combination with the submarine signaling mined speed. If the pilot or operator desires to determine the depth of water beneath the ship,

waves downwardly from the ship. The current variations from oscillator 63. notonly affects de vice 58, but .are also transmitted to the tone filter 62-and transformer 60, and are impressed upon the grid 65 of electroni'elay l8. Correspondingly amplified current variations in the output of electron relay. 18, are further amplified by electron relay 21, to'effect operation of magnetic relay 28. A recordis therefore immediate- When the reflected sound wave is received by the device 58, the current variations thereby produced are likewise impressed upon electron relay 18, and are caused to operate .rnagnetic relay 28. Therefore a record of the reception is likewise made upon the tape of recorder 67. Since the tape moves at a definite predetermined speed, by noting the record upon the tape, the time required for. the reception of the reflected sound Waves can be determined, and the depth of water beneath the ship calculated. The apparatus can be similarly employedto calculate the distance from a given station equipped with means for simultaneously transmitting sound and radio signals.

In addition to making a record of the transmission and reception of submarine signals, it is alsoevident that recorder 67 will record signals which operate the SOS recorder 51, and the alarm circuit 56.

In order to make possible testing of the above apparatus, and to produce a record whereby it can be readily determined whether or not the apparatus has been properly functioning over a certain period, I can provide test means such as a buzzer '71, adapted to be operated by a closer key '72. A small loop circuit '73 can be connected with buzzer '71, and associated with the other apparatus so as to effect a test signal upon 0108-.- ing key 72. Circuit '73 can be in the form of a small dummy antenna associated with the main antenna circuit 13, or can be provided with a coil coupled to the input of electron relay tube 11 as shown. The regulations under which my apparatus is employed can require that the apparatus be tested at regular intervals, by closing key' '72.

If the recorder 6'7 is operated by such a test signal, as is evidenced by the record upon the tape, then the apparatus is properly functioning. If such test signals are made regularly over a long period, examination to the tape from recorder 67 which has been passed thru the recorder during such period, will show that the apparatus has been'properly functioning and tested as required.

I claim: 1

1. In a system of the character described, radio receiving means adapted to be operative continu ously, and adapted to reradiate signal energy,

selectingmeans responsive to a conventional distress signal and connected to said radio means, and alarm means connected to said radio'means and J operative in response to the reception of signal energy of sustained duration from a substantially similar apparatus, said last means being unresponsive to said distress signal and to conventional telegraphic signals.

2. In a system of the class described, continuously functioning radio receiving and regenerating apparatus installed upon a plurality of ships which navigate within the same general locality,

the apparatus on each ship including an antenkey 64 is closed for an instant, to transmit sound a plurality of ships which navigate in the same general locality, the apparatus on each ship including an antenna, an oscillating electron re lay regeneratively connected 'to said antenna, a tuned circuit including'a constantly varying condenser of small capacity whereby the tuning of said circuit is continuously varied within'close limits, and translating means coupled to said' electron relay, the radiations of said apparatus serving as a warning signal to nearby vessels similarly equipped andsaid translating means serving to translate a warning signal from said other vessels."

' WALTER NATHANIEL FANNING. 

